1. Field of the Invention
The present invention relates to a hinge for a refrigerated display case, and, more particularly, to a hinge for a refrigerated display case which is adapted to pivot a door, such as a glass door, about a horizontal axis and hold the door in an upward open position.
2. Description of the Related Art
A refrigerated storage cabinet, such as a chest freezer, includes a top door which pivots about a horizontal axis at the rear of the chest freezer. When loading items into or removing items from the chest freezer, it is necessary that the door remain in an upward open position. To maintain the door in the open position, it is known to utilize a tension spring in conjunction with the hinge, whereby the door is held in the open position.
Refrigerated display cases typically include a glass front wall so that a customer may view the items stored therein. To improve the thermal efficiency of such a display case, the glass door may be formed from thermopane glass, i.e., double pane glass. The thermopane glass door may be hinged at a top edge thereof, and pivot about a horizontal axis. Such thermopane glass is quite heavy when compared with single pane glass, and therefore may be difficult to hold in an open position when loading items into or removing items from the display case, or when cleaning the interior of the display case.
One solution for maintaining a thermopane glass door of a refrigerated display case in an open position is to utilize a hinge equipped with a gas cylinder for biasing the thermopane glass door to the open position. Such a device is disclosed by U.S. Pat. No. 5,116,274 (Artwohl et al). To attach the hinge to the glass, a clamp assembly having two pieces is utilized. The first piece is rigidly attached to the hinge, and a second piece is adjustably connected to the first piece, and coacts with the first piece to sandwich an upper edge of the glass door therebetween.
A problem with a hinge which biases a thermopane glass door to an open position utilizing a gas cylinder is that the gas cylinder has a relatively limited life span. Typically, after a few thousand cycles of opening and closing, the gas cylinder may fail and need to be replaced. Such replacement of the gas cylinder increases the maintenance costs associated with the refrigerated display case. Moreover, upon failure of the gas cylinder, the glass door may no longer be biased to an open position and cause an inconvenience to customers because of the necessity to manually hold the glass door open. Additionally, failure of the gas cylinder may pose a possible safety hazard if the door should fall to the closed position via gravitational force.
What is needed in the art is a hinge assembly for a refrigerated display case which effectively engages the glass door, and biases the glass door to an open position with increased reliability.